Field
The disclosed technology generally relates to semiconductor devices, and more particularly to transistor devices such as metal-oxide-semiconductor (MOS) transistor devices.
Description of the Related Technology
Hot carrier injection (HCI), also known as channel hot carrier (CHC) injection, is a phenomenon known in solid-state electronic devices, where electrons or holes gain sufficient kinetic energy within the channel to overcome a potential barrier of the gate dielectric. In MOS transistors, the energetic charge carriers can be physically injected into the gate dielectric and get trapped in the gate dielectric or the channel/gate dielectric, which can undesirably degrade the switching characteristics of the transistor. When the charge carriers are trapped permanently, the degradation in the switching characteristics can be permanent. The hot-carrier injection is one of the mechanisms that negatively impacts the reliability of solid-state devices, such as MOS transistors.
This phenomena has been known for decades, as well as some proposed solutions, including some fabrication process-based solutions (e.g., smoothening of the junction profile by doping adjustment) and design solutions (e.g. reduction of applied field seen by devices, according to safe operating conditions).
However, as physical scaling continues for transistors, known solutions for mitigating the hot carrier injection may not be sufficient. Thus, there exists a need in the relevant industry for novel transistor devices with reduced CHC effects in scaled devices.